The present invention is with respect to a dialysis solution for use in intraperitoneal dialysis having an osmotically active substance in the form of a saccharide and with at least one further substance for regulation of the electrolyte balance, in the form of an aqueous solution.
Patients with serious renal disorders or with complete renal failure have in the past had to make use of an artificial kidney for treatment every two to three days. In the case of this treatment, in addition to water which was no longer able to be excreted by the patient, metabolic products were taken from the patient's body in a generally short stretch of time, that is to say at a rate which was frequently responsible for complications such as a general malaise, vomiting and the like. Furthermore the patient had to be kept in bed at the time of the treatment and was not able to go on working.
It was for these reasons that there has of late been the development of a new treatment for clearing metabolic products and excess water from the body of a patient with renal disease, which is named intraperitoneal or continuous ambulatory peritoneal dialysis (CAPD), in which a dialysis or irrigation solution is run through a sterile pipe into the patient's peritoneal cavity, so that, using the peritoneum as a dialysis membrane, more or less the same effect as a dialysis filter is produced. The solution is kept in the peritoneal cavity for a certain stretch of time, that is to say till not only the water but furthermore the products of metabolism have been cleared from the patient's body to the desired degree. At the end of the treatment, the bag, in which the solution was stored in the first place before the start of the treatment, is placed at a lower level than the outlet in the body wall of the patient for running the solution out of the patient's body back in to the said bag.
This treatment takes place continuously so that the waste products are able to be cleared from the body at a much slower rate over a given length of time, this being very important for the well-being of the patient and furthermore he or she is on his or her feet and may keep on with normal everyday work. A further useful effect is that this form of treatment puts an end to inflammation of the blood vessels likely to be caused by tubes piercing them, as has been necessary for treatment using artificial kidneys so far.
For clearing excess water from the body of a patient, it is necessary for the aqueous CAPD solution to be made up with a osmotically active substance, that is to say one responsible for causing the water to make its way through the peritoneum into the dialysis solution; furthermore the said solution has to have a certain level of electrolyte for keeping up, or for regulation of the electrolyte balance in the body.
Presently the osmotically active substance which is more widely used than any other for this purpose is glucose, although its effect does become less as dialysis takes place, because it is absorbed in quite large amounts by the body. In fact, glucose levels of as high as 300 mg/100 ml of blood are likely on dialysis, something which is very damaging in the case of diabetes, that frequently goes hand in hand with renal disease. Such a glucose uptake may in fact be responsible for hyperglycemic shocks and it may be seen that the administration of strong glucose solutions will be a metabolic risk factor, seeing that the insulin dosage rate is hard to get worked out for increased blood sugar levels. This question is not to be overlooked because 20% of all renal patients have diabetes. A wrong adjustment of the glucose level may be responsible for conditions even as serious as a diabetic coma.
Furthermore the excess resorption of glucose will be the cause of the patient taking up overly much water, that is to say there is osmosis in the wrong direction (reverse osmosis) and the dialytic effect is turned round and put to an end. Further disorders which are to kept an eye on are the building up of excess fat because of metabolic troubles, hypertriglyceridemia and arterosclerosis caused by the increased glucose uptake.
Because of this undesired resorption of glucose in dialysis, in the prior art experiments have been made with suger substitutes as for example fructose, sorbite, xylite and others, see Proc. Europ. Dial. Transpl. Ass. 6 (1969), page 300; Ann. Intern. Med. 79 (1973) page 511.
One using fructose however the outcome was again the resorption of as high levels as was the case with glucose and the same undesired effects were to be seen, although however fructose is better tolerated by diabetics and may be degraded in the liver quickly. A specially undesired effect is that fructose dialysis solution is the cause of irritation of the peritoneum and for this reason is responsible for an unpleasant feeling on the part of the patient.
The use of polyol-based sugar substitutes such as sorbite is likely to be troublesome inasfar as such substances are not as a rule able to be metabolized and are stored in the body because they are not able to be excreted. Mannite, as a further example, is stored in the brain after being resorbed, and this is likely to be the cause of serious brain damage.
On the other hand, by way of parenteral nutrition, suggestions have been made in German Pat. Nos. 2,035,674, 2,429,034 and 2,642,714 for the use of different sugar components. However parenteral nutrition of a patient by infusion right into the blood is quite different in nature to the use of a CAPD dialysis solution, in which the most important points are clearing excess water from the body and electrolyte exchange. For this reason it is not possible for such parenteral nutrition solutions to take the place of a dialysis solution for CAPD.